Techniques are known in the art in which a vehicle structure member is manufactured by using a hollow extruded material that has a pair of side plates and a plurality of connecting plates connecting the side plates together and that has a quadrilateral closed section and a longitudinal shape, such that the width dimension of the vehicle structure member, or the distance between the side plates, varies in the longitudinal direction of the vehicle structure member. A method for manufacturing a vehicle structure member described in Patent Document 1 is an example of such techniques. In this method, easily bent shape portions such as notches are formed in a pair of connecting plates of a hollow extruded material having a quadrilateral section, and a pair of side plates are pressed by press working so that the connecting plates are partially bent and deformed, whereby the hollow extruded material is thus partially compressed.